Jackson is "the Java JSON library" or "the best JSON parser for Java". Or simply as "JSON for Java".

Jackson Databind Source Code files are provided in the source packge (jackson-databind-2.14.0-sources.jar). You can download it at Jackson Maven Website.

You can also browse Jackson Databind Source Code below:

⏎ com/fasterxml/jackson/databind/type/MapType.java

package com.fasterxml.jackson.databind.type;

import java.lang.reflect.TypeVariable;

import com.fasterxml.jackson.databind.JavaType;

/**
 * Type that represents "true" Java Map types.
 */
public final class MapType extends MapLikeType
{
    private static final long serialVersionUID = 1L;

    /*
    /**********************************************************
    /* Life-cycle
    /**********************************************************
     */

    private MapType(Class<?> mapType, TypeBindings bindings,
            JavaType superClass, JavaType[] superInts, JavaType keyT, JavaType valueT,
            Object valueHandler, Object typeHandler, boolean asStatic) {
        super(mapType, bindings, superClass, superInts,
                keyT, valueT, valueHandler, typeHandler, asStatic);
    }

    /**
     * @since 2.7
     */
    protected MapType(TypeBase base, JavaType keyT, JavaType valueT) {
        super(base, keyT, valueT);
    }

    /**
     * @since 2.7
     */
    public static MapType construct(Class<?> rawType, TypeBindings bindings,
            JavaType superClass, JavaType[] superInts,
            JavaType keyT, JavaType valueT) {
        return new MapType(rawType, bindings, superClass, superInts, keyT, valueT, null, null, false);
    }
    
    @Deprecated // since 2.7
    public static MapType construct(Class<?> rawType, JavaType keyT, JavaType valueT)
    {
        // First: may need to fabricate TypeBindings (needed for refining into
        // concrete collection types, as per [databind#1102])
        TypeVariable<?>[] vars = rawType.getTypeParameters();
        TypeBindings bindings;
        if ((vars == null) || (vars.length != 2)) {
            bindings = TypeBindings.emptyBindings();
        } else {
            bindings = TypeBindings.create(rawType, keyT, valueT);
        }
        // !!! TODO: Wrong, does have supertypes
        return new MapType(rawType, bindings, _bogusSuperClass(rawType), null,
                keyT, valueT, null, null, false);
    }

    @Deprecated // since 2.7
    @Override
    protected JavaType _narrow(Class<?> subclass) {
        return new MapType(subclass, _bindings,
                _superClass, _superInterfaces, _keyType, _valueType,
                _valueHandler, _typeHandler, _asStatic);
    }

    @Override
    public MapType withTypeHandler(Object h) {
        return new MapType(_class, _bindings,
                _superClass, _superInterfaces, _keyType, _valueType, _valueHandler, h, _asStatic);
    }

    @Override
    public MapType withContentTypeHandler(Object h)
    {
        return new MapType(_class, _bindings,
                _superClass, _superInterfaces, _keyType, _valueType.withTypeHandler(h),
                _valueHandler, _typeHandler, _asStatic);
    }
    
    @Override
    public MapType withValueHandler(Object h) {
        return new MapType(_class, _bindings,
                _superClass, _superInterfaces, _keyType, _valueType, h, _typeHandler, _asStatic);
    }

    @Override
    public MapType withContentValueHandler(Object h) {
        return new MapType(_class, _bindings,
                _superClass, _superInterfaces, _keyType, _valueType.withValueHandler(h),
                _valueHandler, _typeHandler, _asStatic);
    }

    @Override
    public MapType withStaticTyping() {
        if (_asStatic) {
            return this;
        }
        return new MapType(_class, _bindings,
                _superClass, _superInterfaces, _keyType.withStaticTyping(), _valueType.withStaticTyping(),
                _valueHandler, _typeHandler, true);
    }

    @Override
    public JavaType withContentType(JavaType contentType) {
        if (_valueType == contentType) {
            return this;
        }
        return new MapType(_class, _bindings, _superClass, _superInterfaces,
                _keyType, contentType, _valueHandler, _typeHandler, _asStatic);
    }
    
    @Override
    public MapType withKeyType(JavaType keyType) {
        if (keyType == _keyType) {
            return this;
        }
        return new MapType(_class, _bindings, _superClass, _superInterfaces,
                keyType, _valueType, _valueHandler, _typeHandler, _asStatic);
    }

    @Override
    public JavaType refine(Class<?> rawType, TypeBindings bindings,
            JavaType superClass, JavaType[] superInterfaces) {
        return new MapType(rawType, bindings,
                superClass, superInterfaces, _keyType, _valueType,
                _valueHandler, _typeHandler, _asStatic);
    }

    /*
    /**********************************************************
    /* Extended API
    /**********************************************************
     */
    
    @Override
    public MapType withKeyTypeHandler(Object h)
    {
        return new MapType(_class, _bindings,
                _superClass, _superInterfaces, _keyType.withTypeHandler(h), _valueType,
                _valueHandler, _typeHandler, _asStatic);
    }

    @Override
    public MapType withKeyValueHandler(Object h) {
        return new MapType(_class, _bindings,
                _superClass, _superInterfaces, _keyType.withValueHandler(h), _valueType,
                _valueHandler, _typeHandler, _asStatic);
    }

    /*
    /**********************************************************
    /* Standard methods
    /**********************************************************
     */

    @Override
    public String toString()
    {
        return "[map type; class "+_class.getName()+", "+_keyType+" -> "+_valueType+"]";
    }
}

⏎ com/fasterxml/jackson/databind/type/MapType.java

Or download all of them as a single archive file:

File name: jackson-databind-2.14.0-sources.jar
File size: 1187952 bytes
Release date: 2022-11-05
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